Method of making a printing sleeve having printing characters around its periphery

ABSTRACT

The method of molding printing characters from synthetic resin material and around the periphery of an endless belt or sleeve member. The method includes setting the sleeve within a circle formed by various printing characters, the sleeve being space from the characters so as to form an annular space therebetween. Synthetic resin material is then poured into the annular space so as to adhere to the sleeve and fill the mold cavities. The material is then cured by heating it and then is cooled to become hard. The resulting sleeve with printing characters formed around its periphery is then removed from the mold.

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naveu'roz K D. Nerrssnsmv BYZXM ATTORNEY United States Patent 3,714,308 METHOD OF MAKING A PRINTING SLEEVE HAV- ING PRINTDIG CHARACTERS AROUND ITS PERIPHERY Raphael D. Nettesheim, New Berlin, Wis, assignor to The Schwaab Label Company, Inc, Milwaukee, Wis. Filed Aug. 18, 1969, Ser. No. 850,859 Int. Cl. B29d 3/02; B413 27/20 US. Cl. 26445 11 Claims ABSTRACT OF THE DISCLOSURE The method of molding printing characters from synthetic resin material and around the periphery of an endless belt or sleeve member. The method includes setting the sleeve within a circle formed by various printing characters, the sleeve being spaced from the characters so as to form an annular space therebetween. Synthetic resin material is then poured into the annular space so as to adhere to the sleeve and fill the mold cavities. The material is then cured by heating it and then is cooled to become hard. The resulting sleeve with printing characters formed around its periphery is then removed from the mold.

BACKGROUND OF THE INVENTION The invention pertains to a method of making printing sleeves having printing characters around the periphery thereof, such printing sleeves being of the type shown in the co-pending United States application, Ser. No. 764,- 540, filed Oct. 2, 1968, now abandoned, and entitled Marking Device. These devices have cylinders rotatably mounted therein with printing characters around the periphery of the cylinder so that the cylinders can be rotated to present any combination of printing characters to the article on which it is desired to print. The invention finds particular utility in devices for stamping dates or other changeable indicia.

The invention finds particular utility when used with a microporous resin material of the type which is capable of storing the marking fluid within its porous structure. Such resin material is of the type shown in the U.S. patent to Leeds, No. 3,055,297, issued Sept. 25, 1962. The advantages of the use of such porous material are known but the material itself is fragile in nature and must be adequately supported when in use.

Marking cylinders having characters around their periphery have heretofore been manufactured by molding the individual printing characters on a flat strip of material and then after curing, it has been the practice to form or curl the strip into a ring and secure it to a cylindrical support. Other forms of prior art methods have been used to form cylindrical marking devices, but generally they have been diflicult and expensive to manufacture, costly to fabricate, and did not adequately support the marking material, particularly if it were made from synthetic resin material such as contemplated by use with the present invention.

SUMMARY OF THE INVENTION The present invention provides a method of making a printing sleeve having printing characters formed around its periphery which includes the steps of arranging printing character molds in a circle and with the negative characters of the molds facing inwardly. The sleeve is then set within the circle of characters and spaced therefrom to form an annular space therewith; liquid material such as synthetic resin which is of micro-porous nature when hard, is then poured into the annular space so as to be bonded or otherwise adhered to the sleeve and comice pletely fill the negative mold characters. Thus, an integrally formed printing sleeve is formed having an inner supporting sleeve and integrally formed characters around the periphery thereof. A more specific object of the invention relates to the use of a central mandrel over which the sleeve is initially mounted for insertion within the circle of character molds, and this central mandrel can then be withdrawn after the material is poured, cured and hardened, thereby permitting easy removal of the completed printing sleeve.

Another more specific object of the invention relates to the application of a vacuum to the mold being made after the first pour of resin material has been completed so as to insure that all air is removed from the molten poured material. After the removal of any air, the mold can be completely filled with additional molten material so as to insure the elimination of any voids in the completed printing member.

Another aspect of the invention relates to the use of a vinyl material for the sleeve member, which vinyl material has a cloth fabric on one side of the sleeve so that the cloth material forms the outer surface of the sleeve; in this manner, the molten resin material adheres firmly to the cloth material and provides a good bond therewith; the inner surface of the finished printing member is then comprised of the vinyl material which offers the necessary strength and rigidity to the finished product and also permits a smooth surface for easy insertion on a cylindrical supporting drum.

These and other objects and advantages of the present invention will appear hereinafter as this disclosure progresses, reference being had to the accompanying drawmgs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a plurality of mold arrangements made for use with the present invention set in a common block;

FIG. 2 is an enlarged, cross sectional view taken generally along the line 2--2 in FIG. 1 and showing one of the mold arrangements with the material pouring means thereabove;

FIG. 3 is a perspective view of a piece of flexible material of which a printing sleeve is made;

FIG. 4 is a view of the sleeve made from the flat piece of FIG. 3;

FIG. 5 is an enlarged edge view of the sleeve shown in FIG. 4;

FIG. 6 is a perspective view of the sleeve shown in FIG. 4 when mounted on a mandrel;

FIG. 7 is a view of the block shown in FIG. 1 inserted in a vacuum chamber, the view being greatly reduced from the FIG. 1 showing;

FIG. 8 is an enlarged, fragmentary view of a portion of the device shown in FIG. 2;

FIG. 9 is a view of the block shown in FIG. 7 after it has been removed from the vacuum chamber and placed in a clamp;

FIG. 10 is a view similar to FIG. 2, but showing the mandrel being withdrawn from the printing sleeve after the pour has been made;

FIG. 11 is a fragmentary plan view of the device shown in FIG. 10 as when the sleeve is being removed from the molds; and

FIG. 12 is a perspective view of the finished printing sleeve.

DESCRIPTION OF A PREFERRED EMBODIMENT The mold assembly shown in FIG. 1 illustrates four separate molding arrangements made in accordance with the present invention and as each of the four arrangements are similar, only one will be referred to in detail. The four arrangements are provided in a common mounting block B so as to facilitate the simultaneous manufacture of a plurality of printing sleeves. Any one printing device of the type shown in the said application, Ser. No. 764,540, may employ four separate printing cylinders to thereby be able to print, for example, the month, date and year. Therefore, all four cylinders for any such marking device can be manufactured simultaneously in a common mounting block B.

As shown in FIGS. 1 and 2, a series of individual printing character molds 1 are arranged in a circle and held in radially extending slots 2 formed in the mounting block, the cavities of each mold facing inwardly towards the center. A hole 3 extends downwardly through the block from that portion of the block in the center of the molds.

The mounting block is preferably formed of steel and has a smooth, flat top surface.

A cylindrical mandrel M is provided and which has a diameter that snugly and slidingly fits within the hole 3. The mandrel has a small marker 3a adjacent its upper peripheral edge.

The sleeve S shown in FIG. 4 is formed from a strip (FIG. 3) or flexible member which includes a vinyl plastic 4 along one side and a roughened fabric material, such as cotton 5, along the other side. The vinyl and fabric material is formed as an integral strip and can be cut in any size desired. This strip of combined material is cut to the desired length and can then be bevelled (as shown clearly in FIG. 3) at each end so that when it is formed into a sleeve member the overlapping ends are heated or otherwise bonded or fused together without any bump or protrusion occurring at the joint 6 so formed. Various suitable means, such as glue, sewing, heat sealing or others, can be used for fastening the ends of the strip together so as to form the tubular sleeve S shown in FIG. 4.

The sleeve is then positioned on the mandrel, as shown in FIG. 6, with the vinyl surface adjacent the mandrel and the cotton surface forming the outer periphery of the sleeve. The joint 6 of the sleeve is positioned directly over the marker 3a on the upper edge of the mandrel so that when the mandrel is inserted in the hole 3, as shown in FIGS. 1 and 2, the joint and the marker 3a can be positioned in between any two of the molds 1. In this manner, any printing character which is formed on the finished printing sleeve PS (FIG. 12) will not be located directly on the joint 6 in the event there is some irregularity at the joint 6.

It will be noted that when the mandrel M is inserted in place in the hole 3, the sleeve S is spaced radially inwardly a distance from the molds 1, forming an annular space 8 therebetween. The bottom of the space 8 is defined by a horizontal flat bottom wall 10 in the block.

A material 11 such as a micro-porous resin material is fully described in the said U.S. Pat. 3,055,297, and a detailed description of it is not believed to be necessary here. It is thought sufficient to say this material, when cured, is of a microporous nature that is capable of storing the printing fluid, such as ink, within its structure. This material when cured is very fragile and diflicult to support, particularly against the pressures required for printing.

In accordance with the invention, this material 11, in its liquid form, is poured into the space 8 between the molds 1 and the sleeve S, so as to fill the mold cavities and adhere to the roughened fabric surface of the sleeve.

For the purpose of insuring that no air remains in the annular space 8 after the latter has been filled, a series of hollow tips 12 (FIG. 2) are inserted down into the annular space with their discharge ends adjacent the bottom wall 10. As the material 11 flows from the container 14 and through the tips 12 to the bottom of the space, the space fills and the tips are gradually raised as the filling of the space proceeds.

When the space 8 has been preliminary filled, certain air pockets may exist within the material and in order to form perfect printing characters on the periphery of the sleeve, it is necessary that all of the air be expelled from the molten material 11 before it hardens. Therefore, to insure that all air is removed, the material is submitted to a vacuum pressure, for example, as being inserted in a chamber 16 (FIG. 7). If any excess air is in the material, the vacuum forces it to rise out of the material, consequently causing the remaining material to sink or become depressed slightly in certain areas. If this occurs, additional liquid material is poured in the space to completely fill these voids, as shown in FIG. 8.

After the space is completely filled, a steel plate 18 (FIG. 9) is placed over the filled space and molds, and a small amount of pressure is exerted on top of the plate,

as by a screw clamp 19, to squeeze the flash or excess material from the top of the filled space, to thereby insure that no flash edges remain in the finished sleeve after the material has cured.

The material is cured as follows. Heat is applied to the material, by means, for example, of an electrical heating unit U located in the plate 18. After the heating process, the material is then cooled, of a hard nature and bonded integrally with the fabric of the sleeve.

To remove the sleeve, the plate 18 is removed and the center mandrel M pulled downwardly (FIG. 10), thereby sliding the mandrel ofl the vinyl surface 4 of the sleeve. It is then only necessary to grasp the sleeve S by its inner edge (FIG. 11) and pull it out from contact with the molds and lift it out of the block.

The finished printing sleeve PS (FIG. 12) has an internal surface 4 formed by the vinyl which provides exceptionally good strength for the entire assembly, and which strength the resin material by itself is incapable of supplying. The vinyl also has a smooth surface so that it can be readily assembled on the supporting cylinder (not shown) of the type shown in the U.S. application, Ser. No. 764,540. The fabric portion 5 of the sleeve S which is formed integrally with the vinyl has the finished printing characters firmly bonded thereto.

The present invention provides a method for molding a printing sleeve in its final form, that is, it is made in one process in a ring form with a strong inner portion and accurate characters on its periphery.

I claim:

1. A method of making a printing sleeve having printing characters formed around its periphery comprising, arranging a series of printing character molds in a circle, arranging a flexible sleeve having a cloth surface on one side and a smooth vinyl surface on the other side so that said cloth surface faces radially outwardly and the sleeve is capable of adding strength and rigidity to the final product, inserting said sleeve with said outer surface of cloth facing radially outwardly and within said circle and with the individual character molds surrounding and facing said sleeve and spaced therefrom to form an annular space therewith, filling said space and consequently said character molds with a liquid synthetic resin material which when hardened is micro-porous and is fragile in nature and must be supported when in use, whereby said resin material adheres to said outwardly facing surface of cloth, curing said resin to thereby harden it, and removing said sleeve from said molds.

2. A method of making a printing sleeve having printing characters formed around its periphery comprising, arranging a flexible sleeve having a roughened fabric material side facing outwardly and the sleeve is capable of adding strength and rigidity to the final product, inserting said sleeve over a cylindrical mandrel, arranging a series of printing character molds in a circle and inserting said sleeve and mandrel within said circle and with the individual character molds surrounding and facing said sleeve and spaced therefrom to form an annular space therewith, filling said space and consequently saidcharacter molds with a liquid synthetic resin material which when hardened is micro-porous and is fragile in nature and must be supported when in use, whereby the latter is bonded integrally with the roughened fabric side of said sleeve, curing said resin to thereby harden it, withdrawing said mandrel from said sleeve, and removing said sleeve from said character molds.

3. A method of making aprinting sleeve having printing characters formed around its periphery comprising, arranging a series of printing character molds in a circle, arranging a flexible sleeve having a cloth surface on one side and a smooth vinyl surface on the other side so that said cloth surface faces radially outwardly, inserting said sleeve with said outer surface of cloth facing radially outwardly and within said circle and with the individual character molds surrounding and facing said sleeve and spaced therefrom to form an annular space therewith, said sleeve being capable of adding strength and rigidly to the final product, filling said space and consequently said character molds with a liquid synthetic resin material which When hardened is micro-porous and is fragile in nature and must be supported when in use, applying a vacuum pressure to said material to draw any excess air therefrom, pouring additional resin material in the space to completely fill said space and said molds to bond said material to said outwardly facing surface of cloth, curing said resin to thereby harden it, and removing said sleeve from said molds.

4. A method of making a printing sleeve having printing characters formed around its periphery comprising, arranging a series of printing character molds in a circle, arranging a fiexible sleeve having a cloth surface on one side and a smooth vinyl surface on the other side so that said cloth surface faces radially outwardly and the sleeve is capable of adding strength and rigidity to the final product, inserting said sleeve with said outer surface of cloth facing radially outwardly and within said circle and with the individual chracter molds surrounding and facing said sleeve and spaced therefrom to form an annular space therewith, filling said space and consequently said character molds with a liquid synthetic resin material which when hardened is micro-porous and is fragile in nature and must be supported when in use, whereby said resin material adheres to said outwardly facing surface of cloth, covering said material and said molds with a plate and applying presure to said plate to remove excess material from the top of the filled space, and heating said material and then cooling it to thereby cure said material, and removing said sleeve from said molds.

5. A method of making a printing sleeve having printing characters formed around its periphery comprising, arranging a series of printing character molds in a circle, arranging a tflexible sleeve having a cloth surface on one side and a smooth vinyl surface on the other side so that said cloth surface faces radially outwardly, inserting said sleeve with said outer surface of cloth facing radially outwardly and within said circle and with the individual character molds surrounding and facing said sleeve and spaced therefrom to form an annular space therewith, said sleeve being capable of adding strength and rigidity to the final product, filling said space and consequently said character molds with a liquid synthetic resin material which when hardened is micro-porous and is fragile in nature and must be supported when in use, whereby said resin material adheres to said outwardly facing surface of cloth, heating said molds and material for a period of time, cooling said material to thereby harden it, and removing said sleeve from said molds.

6. A method of making a printing sleeve having printing characters formed around its periphery comprising, arranging a flexible sleeve having a cloth surface on one side and a smooth vinyl surface on the other side so that said cloth surface faces radially outwardly and the sleeve is capable of adding strength and rigidity to the final product, inserting said sleeve over a cylindrical mandrel, arranging a series of printing character molds in a circle and inserting said sleeve and mandrel within said circle and with the individual character molds surrounding and facing said sleeve and spaced therefrom to form an annular space therewith, filling said space and consequently said character molds with a liquid synthetic resin material which when hardened is micro-porous and is fragile in nature and must be supported when in use, applying a vacuum pressure to said material to draw any excess air therefrom, pouring additional resin material in the space to completely fill said space and said molds to bond said material to said outwardly facing surface of cloth, curing said resin to thereby harden it, and removing said sleeve from said molds.

7. A method of making a printing sleeve having printing characters formed around its periphery comprising, inserting a sleeve over a cylindrical mandrel, arranging a flexible sleeve having a cloth surface on one side and a smooth vinyl surface on the other side so that said cloth surface faces radially outwardly and the sleeve is capable of adding strength and rigidity to the final product, arranging a series of printing character molds in a circle and inserting said sleeve and mandrel within said circle and with the individual character molds surrounding and facing said sleeve and spaced therefrom to form an annular space therewith, filling said space and consequently said character molds with a liquid synthetic resin material which when hardened is micro-porous and is fragile in nature and must be supported when in use, whereby said resin material adheres to said outwardly facing surface of cloth, covering said material and said molds with a plate and applying pressure to said plate to remove excess material from the top of the filled space and heating said material and then cooling it to thereby harden it, withdrawing said mandrel from said sleeve, and removing said sleeve from said character molds.

8. A method of making a printing sleeve having printing characters formed around its periphery comprising, arranging a series of printing ch'aracter molds in a circle arranging a flexible sleeve having a cloth surface on one side and a smooth vinyl surface on the other side so that said cloth surface faces radially outwardly and the sleeve is capable of adding strength and rigidity to the final product, inserting said sleeve Within said circle and with the individual character molds surrounding and facing said sleeve and spaced therefrom to form an annular space therewith, filling said space and consequently said character molds with a liquid synthetic resin material which when hardened is micro-porous and is fragile in nature and must be supported when in use, applying a vacuum pressure to said material to draw any excess air therefrom, pouring additional resin material in the space to completely fill said space and said molds to bond said material to said outwardly facing surface of cloth, covering said material and said molds with a plate and applying pressure to said plate to remove excess material from the top of the filled space, and heating said material and then cooling it to thereby harden it, and removing said sleeve from said molds.

9. A method of making a printing sleeve having printing characters formed around its periphery comprising, arranging a fiexible sleeve having a cloth surface on one side and a smooth vinyl surface on the other side so that said cloth surface faces radially outwardly and the sleeve is capable of adding strength and rigidity to the final product, inserting said sleeve over a cylindrical mandrel, arranging a series of printing character molds in a circle and inserting said sleeve and mandrel within said circle and with the individual character molds surrounding and facing said sleeve and spaced therefrom to form an annular space therewith, filling said space and consequently said character molds with a liquid synthetic resin material Which when hardened is micro-porous and is fragile in nature and must be supported when in use,

applying a vacuum pressure to said material to draw any excess air therefrom, pouring additional resin material in the space to completely fill said space and said molds to bond said material to said outwardly facing surface of cloth, covering said material and said molds with a plate and applying pressure to said plate to remove excess material from the top of the filled space, and heating said material and then cooling it to thereby harden it, withdrawing said mandrel from said sleeve and removing said sleeve from said character molds.

10. A method of making a printing sleeve having printing characters formed around its periphery comprising, arranging a cflexible sleeve having a cloth surface on one side and a smooth vinyl surface on the other side so that said cloth surface faces radially outwardly and the sleeve is capable of adding strength and rigidity to the final product, inserting said sleeve over a cylindrical mandrel, arranging a series of printing character molds in a circle and inserting said sleeve and mandrel within said circle and with the individual character molds surrounding and facing said sleeve and spaced therefrom to form an annular space therewith, filling said space and consequently said character molds with a liquid synthetic resin material which when hardened is micro-porous and is fragile in nature and must be supported when in use, whereby said resin material adheres to said outwardly facing surface of cloth, heating said molds and material for a period of time, cooling said material to thereby harden it, withdrawing said mandrel from said sleeve, and removing said sleeve from said character molds.

11. A method of making a printing sleeve having printing characters formed around its periphery comprising, arranging a series of printing character molds in a circle, arranging a flexible sleeve having a cloth surface on one side and a smooth vinyl surface on the other side so that said cloth surface faces radially outwardly and the sleeve is capable of adding strength and rigidity to the final product, inserting said sleeve within said circle and with the individual character molds surrounding and facin said sleeve and spaced therefrom to form an annular space therewith, filling said space and consequently said character molds with a liquid synthetic resin material which 'when hardened is micro-porous and is fragile in nature and must be supported when in use, applying a vacuum pressure to said material to draw any excess air therefrom, pouring additional resin material in the space to completely fill said space and said molds to bond said material to said outwardly facing surface of cloth, heating said molds and material for a period of time, cooling said material to thereby harden it, and removing said sleeve from said molds.

References Cited UNITED STATES PATENTS 1,991,009 2/1935 Browne et al. 264-225 X 2,222,755 11/1940 Watson 264-275 X 2,598,806 6/1952 Lauer 101-103 2,941,905 6/ 1960 Hofmann 117-232 3,045,290 7/1962 Anderson et al. 2'64-275 X 3,055,297 9/1962 Leeds 101-327 3,100,676 8/1963 Christie 264-275 3,101,668 8/1963 Leeds 264-226 X 3,184,828 5/1965 Dawes, Jr, 264-275 X 3,253,542 5/1966 McDonough 101-367 3,287,485 11/1966 McCord 264-263 3,380,121 4/1968 Chittenden et al. 2-64-94 X 3,420,925 1/1969 Sharif 264-225 X 3,484,516 12/1969 Simons 264-275 X 3,501,564 3/ 1970 Snoeyenbos et al. 264-255 ROBERT F. WHITE, Primary Examiner A. M. SOKAL, Assistant Examiner U.S. Cl. X.R. 

